Security

Security in Cloud Computing
Thanks to Research talk at UA | Ragib Hasan |
www.ragibhasan.com | UAB CIS 12/02/11
Calvin Vreeland
Security
• How do you know data in cloud is safe and
secure?
• Even reputable providers can be hacked
What the “experts” are
saying?
[Cloud Computing] is a
security nightmare and it
can't be handled in
John Chambers traditional ways.
CISCO CEO
It’s stupidity. It’s
worse than stupidity
Richard Stallman
GNU 3
Businesses don’t trust clouds (yet)
Almost 75%
of business
CFOs are still
afraid to use
clouds for
sensitive
data due to
lack of
security
4
Traditional systems security
vs
Cloud Computing Security
Securing a traditional Securing a cloud
system
5
Traditional systems security
vs
Cloud Computing Security
Analogy
Securing a house Securing a motel
Owner and user are Owner and users are almost
often the same entity invariably distinct entities
6
Traditional systems security
vs
Cloud Computing Security
Securing a house Securing a motel
Biggest user concerns Biggest user concern
Securing perimeter Securing room against
Checking for intruders (the bad guy in next
Securing assets room | hotel owner)
7
Cloud security involves securing across
multiple dimensions of the cloud
Data and computation
integrity and confidentiality
Infrastructure,
Data Privacy topology
Networking Forensics
8
Research on Cloud Computing
Security: A High Level View
• Novel attacks
• Trustworthy cloud architectures
• Data integrity and availability
• Computation integrity
• Data and computation privacy
• Data forensics
• Misbehavior detection
• Malicious use of clouds
• Economic attacks
9
Co-tenancy in clouds creates new
attack vectors
A cloud is shared by multiple users
Malicious users can now legally be in the
same infrastructure
Misusing co-tenancy, attackers can
launch side channel attacks on victims
any attack based on information gained from the physical
implementation of a cryptosystem, rather than brute force or
theoretical weaknesses in the algorithms. E.g., timing information,
power consumption, electromagnetic leaks or even sound can
provide an extra source of information which can be exploited to
break the system
Example: the Topology attack on Amazon EC2 (“Hey You! Get
off of my Cloud …” CCS 2009) 10
Today’s cloud architectures act like
big black boxes
Clients have no idea of or control over what is
happening inside the cloud
Clients are forced to trust cloud providers completely
Existing Approaches: TCCP (uses TPM), CloudProof
The Trusted Platform Module (TPM) installed on certain motherboards is
an extra chip that is designed to aid in the generation of certain types of
cryptographic keys to use in various parts of the computer.
11
Today’s clouds provide no guarantee
about outsourced data
Problem:
Dishonest cloud providers can throw data away or lose data.
Malicious intruders can delete or tamper with data.
Clients need reassurance that the outsourced data is
available, has not been tampered with, and remains
confidential.
Example Approaches: Provable Data Possession (PDP), Proof of
Retrievability (PoR), HAIL
12
Ensuring confidentiality of data in
outsourced computation is difficult
Most type of computations require decrypting data before
any computations
If the cloud provider is not trusted, this may result in
breach of confidentiality
Existing Approaches: Homomorphic encryption, TCCP
13
Privacy is often the victim when using
a cloud …
It is almost impossible to provide privacy of sensitive
personal information in computation outsourcing
Using Google spreadsheets to maintain SSN
Popular distributed computation systems such as
MapReduce are NOT designed with privacy in mind
14
Clients have no way of verifying
computations outsourced to a Cloud
Scenario
User sends her data processing job to the cloud.
Clouds provide dataflow operation as a service (e.g., MapReduce, Hadoop etc.)
Problem: Users have no way of evaluating the correctness of results
Existing Approaches: Runtime Attestation, Majority voting, Redundant operations
15
Assessing the Capability of a Cloud Provider
is difficult due to the black box model
Availability, fault-tolerance, and resilience are important to
clients for mission-critical data
But cloud providers do not want to reveal their capability
or redundancy
So, clients need a way to remotely verify the capability
claims
16
Data Forensics in Clouds is difficult
Certain Government regulations mandate the ability to audit
and run forensic analysis on critical business or healthcare data
Clouds complicate forensic analysis, since the same storage
infrastructure is shared by many clients
Cloud providers are not willing to open up their
entire storage for forensic investigations.
17
Clouds can be used for malicious
purposes
Adversaries can rent clouds
temporarily to create a large scale
botnet very quickly
Clouds can be used for spamming,
Denial of service, brute force
password breaking, and other
attacks
Example: WPACracker.com – Claims to break WPA passwords for
$17 in under 20 minutes, using a cloud
18
Economy matters!
Sometimes, economic targets are more effective
than technical targets
Attacks can target economic viability of cloud users
(by consuming extra resources), or of cloud providers
(by fraudulently consuming cloud resources)
19
Hassan strategy
Question: How can we make clouds more accountable?
Approach: By maintaining secure and verifiable provenance
chains for all data and computations outsourced to a cloud,
clients can get more accountability.
Provenance of data Provenance of computations
What happened to the data object How was a particular result
while it was inside the cloud? (i.e., computed inside a cloud?
entire history of the data object)
Challenges: How to ensure correct collection of provenance inside a cloud,
even when the cloud provider may not be trustworthy?
Owner, source
History of ownership of a valued object
(Largely) Unexplored Areas
Legal/policy issues and regulatory compliance:
How does cloud computing fit in with data security laws
and regulations such as SOX, HIPAA?
Sarbanes Oxley – result of Enron, accuracy of financial
reporting data
For example,
If I store my data in Amazon, can the Govt. subpoena Amazon
to access my data without violating 4th amendment?
unreasonable search and seizure
Will a cloud based storage system comply with SOX?
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Issues related to users of the cloud
• Sensitive Information
– SLA may allow access and catalog and use info in ways
never intended
• Share data with marketing firm
– Google’s policy – company will share data with gov if “good
faith belief” access is necessary to fulfill lawful requests
– Government can more easily subpoena 3rd party than
privately owned
– Closed Subpoena – provider legally prohibited from telling
customers data has been given to the government
– Google’s problem or SLA may say not responsible
Today’s clouds provide no guarantee
about outsourced data
Amazon’s Terms of services
23
The government – yes it can be good
– Governmental regulations:
• If doing business for EU, cannot store in US
• If credit card data, restrictions on where can store data,
cannot allow free block to be included in another
customer’s block of storage
Examples of problems
• AOL releated 650k customer search terms on
public web page
• MS released search data to US DOD in child
porn case
• British gov misplaced 25 M taxpayer records
• Retailers lose credit card numbers
Anecdotes
“A short account of an interesting or amusing nature”
Why?
Locked Out
Nick Saber isn’t happy now. Monday afternoon, after lunch, Nick came back
from lunch to find out that he couldn’t get into his Gmail account. Further, he
couldn’t get into anything that Google made (beside search) where his
account credentials once worked. When attempting to log in, Nick got a single
line message:
Sorry, your account has been disabled. [?]
That’s it.
No, Google, that’s not it. Somewhere, deep inside the bowels of Google-land,
something went wrong and an innocent person suffers the loss of his data.
This is serious failure!
One point the story highlights is a hard lesson for users: Don’t trust the cloud
at this early stage in its evolution.
http://blogs.zdnet.com/projectfailures/?p=958
Cloud Goes Dark
Amazon.com Web Service's hosted storage service went down Friday
morning, frustrating many Web site customers and refreshing concerns with
the ballyhooed approach of cloud computing.
An online forum spiked with customer complaints Friday morning as some
people found that content stored on Amazon's Simple Storage Service (S3)
was unavailable or performed slowly.
The service was restored a few hours later, according to an Amazon
technician. The first forum posting was timed at 5 a.m. PT, and the service
was back up at just past 9 a.m.
The glitch sent a ripple through the blogosphere as Web entrepreneurs, who
are increasingly using Amazon's hosted computing services, pondered
whether they needed a back-up plan or a more traditional hosting provider.
On the forum, some people complained about how the service glitch
essentially put them out of business temporarily.
http://news.cnet.com/8301-17939_109-9873068-2.html
Google Docs Down
Google's Documents and Spreadsheets service went down for approximately
45 minutes earlier this morning.
The service, Google's online productivity suite, went from having some
features not working, like the log-out button and the document creation drop-
down menu, to coming up with a 404 page.
The downtime calls into question the importance that online Web applications
play in business use, as well as how Google's free document services have
come to replace software solutions such as Microsoft Office for some users or
teams that use Google's real-time collaboration features.
http://news.cnet.com/8301-17939_109-9985608-2.html
Digital Railroad
"Everyone is downloading now and their FTP has slowed to a crawl," one Digital Railroad
member told News Photographer magazine earlier this afternoon, before the site went dark.
It's estimated that there may have been as many as 1,900 client archives on Digital Railroad's
servers as of today.
http://www.nppa.org/news_and_events/news/2008/10/digitalrailroad.html
Security Benefits in the Cloud
• Centralized data – can make it more secure
• Reduced data loss (12K laptops lost in US
airports)
– How secure are laptops?
• If limit employee downloads, can limit data loss
• Easier to monitor security if only one location
• Can move data to another machine
• Logging is better in the cloud (C2 audit trail)
– High overhead, but the cloud can handle it
Security Benefits in the Cloud
• Security bundled in, no need to buy 3rd party
security SW
• Can perform patches and upgrades offline, test
off-line versions of production environment
• Vendors more likely to develop more efficient
security SW
• SaaS/PaaS providers do security testing (lower
cost for security testing split amongst all users)
Regulatory Issues
• No existing regulation
• Despite its size, Google could still fail (look at
GM or those banks that were too big to fail…)
• Government backed insurance?
• Should government regulate the cloud?
– Safe guard for loss or theft?
• Who owns the data?
– Law enforcement easier access to cloud than PC?
Regulatory Issues
• Do people really understand privacy and security
implications of email, Facebook, etc?
• US courts ruled private data in cloud does not have
same level of protection from law enforcement
searches
• 49% concerned if cloud shared files with law
• 80% concerned if used photos for marketing
• 68% concerned is used personal information for
personalized ads
• 63% concerned if provider kept data after used
deleted
Regulatory Issues
• Should government agencies store data on
clouds?
• Procurement regulations will have to change
• GSA pushing for cloud to reduce energy
• US gov. spends $480 M on electricity for
computers
Security in Clouds
• Security hackers:
– Sell proprietary info to competition
– Encrypt storage until pay (ransom/blackmal?)
– Erase everything to damage business
– DDOS, botnets attack network
• Tokyo firm pay $31K to stop it
– Not even clear who should pay ransom
• In a cloud at the mercy of their security
measures
Final Observations: What’s wrong
with today’s cloud security research
Failure to look at reality
– Many security schemes impose unrealistic overheads (e.g.,
>35%!!) – no one will use them in real life clouds
Failure to consider economy
– Security schemes would cause significant changes to
existing cloud infrastructures
– Many attacks simply don’t make any economic sense
Lack of realistic threat models
– Many papers present unrealistic threat models, (“Solutions
in search of a problem”)
38
Clouds can be used for malicious
purposes
Adversaries can rent clouds
temporarily to create a large scale
botnet very quickly
Clouds can be used for spamming,
Denial of service, brute force
password breaking, and other
attacks
Example: WPACracker.com – Claims to break WPA passwords for
$17 in under 20 minutes, using a cloud
39
Cloud Computing......
Design for Disaster?